Methods for inactivating, on medical instruments and devices, viruses containing rna and dna, and apparatuses for implementating same

ABSTRACT

Methods and apparatuses for inactivating RNA and DNA within viruses situated on medical instruments. Through the use of photochemicals and photoactivation by monochromatic light, medical instruments can be rendered safer. 
     A solution of methylene blue having a concentration of 0.01-0.02% by means of interaction with light in the emission spectrum of monochromatic emitters having wavelengths ranging between 582 and 592 nm or between 658 and 662 nm and an overall light output of at least 280 lumens (lm), wherein the instruments are kept in said solution for about 90 minutes.

CROSS REFERENCE TO RELATED PATENT APPLICATIONS

The present invention is a continuation of U.S. patent application Ser.No. 15/119,791, filed Oct. 29, 2014, entitled “METHODS FOR INACTIVATING,ON MEDICAL INSTRUMENTS AND DEVICES, VIRUSES CONTAINING RNA AND DNA, ANDAPPARATUSES FOR IMPLEMENTATING SAME,” which is a United Statesnationalization of PCT/UZ2015/000001, filed May 13, 2015, entitled“METHOD OF RNA AND DNA VIRUSES INACTIVATION ON MEDICAL INSTRUMENTS AND ADEVICE FOR ITS IMPLEMENTATION,” which claims priority from UzbekistanianPatent Application No. IAP 2014 0210, filed May 23, 2014, of the samename, the subject matters of which are incorporated by reference hereinin their entirety.

TECHNICAL FIELD

The invention is generally related to photodynamic inactivation of RNAand DNA viruses on medical instruments.

BACKGROUND OF THE INVENTION

During the last years of the 20th Century and at the beginning of the21st Century, there have been a number of virus-related deaths acrossthe world, with a high risk of threat for humankind's survival. Also, agrowing number of people are being infected, especially with hepatitis B(hereinafter—HBV), and hepatitis C (hereinafter HCV), mostly infected byvirus-laden medical instruments (surgical, dental, ophthalmic,gynecologic and others), which cannot be sterilized enough under hightemperature or by autoclaving. Also, HBV and HCV are resistant to manydisinfectants used in medicine. Thus, the complete removal of viralparticles from the surface of medical instruments and mechanical methodsare not feasible. Consequently, virus particles capable of replicationand infecting people are stored on the medical tools themselves. Forhuman infection and disease development, the existence of even oneparticle of HBV or HCV in blood is enough. This leads to a high risk ofcontracting viral infections of patients with medical procedures.Consequently, there is an urgent need to develop a more effective methodfor the inactivation (deprivation of the ability to replicate) of RNAand DNA viruses and particles on medical instruments.

It is clear that photodynamic inactivation of DNA and RNA viruses isbased on the ability of some chemical substances (photosensitizers),when exposed to light, change to a photoactive condition and generateactive forms of oxygen. The abovementioned forms of oxygen are highlytoxic compounds, which make for photodynamic activities that areemployed in practicing the present invention.

There is a known method of inactivating viruses in biological fluids byprocessing a biological fluid with light for the inactivation ofcontaminants, such as viruses. According to this method light intensityof at least 30 mW/cm² which affect the biological fluid is created.Biological fluid includes a certain amount of the photochemical agent(photosensitizer). When the interaction of the photochemical agent witha light-activated, photochemical agent takes place, it provides viralinactivation.

A famous method is based on the activation of methylene blue in itsinteraction with light having an intensity of at least 30 mW/cm².Methylene blue may be disposed within a biological fluid, and mayinteract with the light for a period between approximately 0.3 and 30minutes. According to the invention, the use of known high intensitylight with a biological fluid, such as blood or blood plasma containinga predetermined amount of methylene blue, enhances the effect ofmethylene blue in killing viruses. Methylene blue is activated by highintensity light having wavelengths from about 550 nm to 700 nm, with apeak at 663 nm. The light absorption in this range provides theactivation of methylene blue. Also, the prior art shows techniques forcreating high-intensity light using high pressure sodium lamps.

However, the use of these known methods for inactivating RNA and DNAcontaining viruses on instruments is not effective because of thehigh-energy intensity, the structural complexity and laboriousness ofthe required operation necessary.

Also, existing techniques for the inactivation of RNA and DNA virusesfor medical instruments are also shown in certain medical fields andtheir instruments, e.g., dental, gynecological, surgery, ophthalmic, andsuch, where, after use, the instruments are subjected to preliminarymechanical treatment and water washing with detergents (soap solution,washing powder). Here, after thorough rinsing with tap water, theinstruments are immersed in a cuvette instrument filled with a solutionof methylene blue. The Cuvette with the tools are so immersed in thecamera setup on a rotating pan. Unit door tightly closed, the timer isset exposure time include monochromatic light emitter is mounted abovethe cuvette, and the motor rotation pan. The process of inactivation ofviruses on the surface of medical instruments in this fashion continuedfor 45 minutes, while processing with monochromatic light of wavelength590 nm.

However, the usage of these known methods of DNA and RNA virusinactivation techniques on medical instruments are not also effectivedue to the increased energy intensity and structural complexity. Inaddition, given that the methylene blue (a photochemical agent) iscapable of providing maximum activation only in the interaction withmonochromatic light of wavelength 590 nm, current methodologies neitherdisclose nor suggest the particular methodologies and apparatuses, asset forth in the instant Specification.

SUMMARY OF THE INVENTION

A primary goal of the present invention is to develop an efficient, withminimal labor and energy consumption, method for inactivating RNA andDNA viruses on medical instruments, by achieving maximum activation ofthe photochemical agent in the interaction with monochromatic light.

This aim is achieved by a preferred method of inactivation of RNA andDNA viruses on medical instruments, according to the principles of thepresent invention, includes a preliminary mechanical cleaning andwashing of the infected tools, their subsequent exposure in an aqueoussolution of methylene blue, with a maximum activation of the interactionof monochromatic light with a solution, preferably in an aqueous0.01-0.02% solution of methylene blue concentration, providing maximalactivation. Further, the inactivation is effected by interaction withlight in the spectrum of monochromatic radiation emitters withwavelength range of 658-662 nm and 582-592 nm or tools kept in thesolution for 90 minutes.

A feature of the claimed process is that the methylene blue solution isradiated by monochromatic light flux with wavelength 590 nm or 660 nm,which corresponds to the wavelength of the absorption spectrum ofmethylene blue. For this purpose, a special source of radiation in theemission spectrum monochromatic emitters with a wavelength range of582-592 nm, and, accordingly the maximum specific content of amonochromatic beam at 590 nm wavelength and the emission spectrummonochromatic emitters with a wavelength range 658-662 nm and thespecific content of monochromatic beam with maximum wavelength of 660nm.

The appropriateness of the aforementioned methylene blue wavelength andthe wavelength of monochromatic light flux is the photoactivation ofmethylene blue. When sufficient photoactivation quantum energy moleculesof methylene blue are absorbed, the electrons excite in their atoms. Asa result, the molecules themselves become sources of scattered light ofthe same wavelength (classical scattering).

Under the influence of light quanta, emitted by the photoactivatedmolecules of methylene blue, there is photoactivation of molecules,which are in the “shadow” relating to monochromatic radiatorinstallation. Thus, to so treat with photoactivation of methylene bluemolecule, as in the path of light rays emitter, all molecules in directcontact, and all that are in the “shadow” relative to it, realizes thefull effect of the treatment, i.e., the sterilization necessary.Inactivation of RNA and DNA viruses for medical instruments can becarried out in a room-temperature photoactivated liquid, e.g., a0.01-0.02% solution of methylene blue (Methylene Blue).

In one example, the aforementioned 0.01-0.02% methylene blue solutionwas subjected to a monochromatic light flux wavelength 590 nm or 660 nm,which corresponds to the wavelength of the absorption spectrum ofmethylene blue.

Preferably, a monochromatic light beam wavelength from 660 nm to 590 nmor a monochromatic emitter is created. Total energy consumption ofdevices implementing the light treatment is preferably about 50 W, andthe light output must be at least 280 lumens (lm). Under the influenceof monochromatic light flux wavelength of 590 nm or 660 nm(corresponding to the wavelength of the absorption spectrum of methyleneblue) the photoactivation of methylene blue molecules occurs.Photoactivated molecules of methylene blue actively enter into a strongbond with a pair of nucleic acids, e.g., guanine and cytosine, and locksthem in the chain of RNA or DNA viruses. Viruses with such inactivatedRNA and DNA, when later entering a person's blood, are thus not capableof destroying cells and replicating inside host cells. It means thatthey completely lose their virulence and pathogenic properties (abilityto infect and cause disease). Moreover, the photoactivated molecules ofmethylene blue promote the formation of reactive atomic oxygen, whichstrengthens the denaturation process of nucleic acids of RNA and DNAviruses.

Methods for the aforementioned inactivation are shown in the variousembodiments set forth in more detail hereinbelow.

BRIEF DESCRIPTION OF DRAWINGS

While this Specification concludes with claims particularly pointing outembodiments and distinctly claiming the subject matter that is regardedas forming the present invention, it is believed that the invention willbe better understood from the following Description taken in conjunctionwith the accompanying Drawings, where like reference numerals designatelike system signal flow and other mechanical elements, in which:

FIG. 1 illustrates an exemplary apparatus for the inactivation of RNAand DNA of viruses on medical and other instruments placed therein andtreated pursuant to the principles set forth in the presentSpecification;

FIG. 2 illustrates another exemplary embodiment of the presentinvention, showing various interior components that may be employed inpracticing the teachings of the present invention, and which may bevisible upon opening a door of an apparatus, such as shown in FIG. 1,and allowing interaction with the interior and the sealing thereof fortreatment;

FIG. 3 is a cross-sectional view of the apparatus shown and described inconnection with FIGS. 1 and 2, generally taken along the indicated A-Aline shown in FIG. 1; and

FIG. 4 is a cross-sectional view of the apparatus shown and described inconnection with FIGS. 1 and 2, generally taken along the indicated B-Bline shown in FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

The following detailed description is presented to enable any personskilled in the art to make and use the invention. For purposes ofexplanation, specific nomenclature is set forth to provide a thoroughunderstanding of the present invention. However, it will be apparent toone skilled in the art that these specific details are not required topractice the invention. Descriptions of specific applications areprovided only as representative examples. Various modifications to thepreferred embodiments will be readily apparent to one skilled in theart, and the general principles defined herein may be applied to otherembodiments and applications without departing from the scope of theinvention. The present invention is not intended to be limited to theembodiments shown, but is to be accorded the widest possible scopeconsistent with the principles and features disclosed herein.

Medical instruments, such as dental, gynecological, surgical, ophthalmicand others, after being used in patients, are subjected to preliminarymechanical cleaning and washing in water with detergents (soapy water,detergents). Thereafter, these instruments are rinsed thoroughly in tapwater and then immersed into a round cuvette device in 0.01-0.02%solution of methylene blue. The instruments or tools are put on thebottom of the cell stack in a single layer so that they are completelycovered with the aforementioned solution of methylene blue. Then, thecell stack with the tools are mounted on the base of the camera unit.With the unit door tightly closed, the timer is set to the selectedexposure time toggle switch. At the same time the door is securelyclosed and till deactivation the timer should not be opened. When thedevice of the camera automatically turns on the panel radiatormonochromatic light mounted above the cuvette. The process ofinactivation of viruses present on the surface of medical instruments.

After switching off the timer, the device board's door is opened, andthe cell stack with the tools is extracted. The tools are removed fromthe solution with tweezers and the methylene blue is rinsed offthoroughly in distilled water. Thereafter, the conventional tools may befurther sterilized.

The photoactivatable fluid to inactivate DNA or RNA viruses ispreferably a 0.01-0.02% solution of methylene blue (Methylene Blue) indistilled water. A 0.01-0.02% solution photoactivated liquid ispreferably prepared by dissolving Methylene Blue, respectively 1.0-2.0g, in 10 liters of distilled water in a clean container.

The aforementioned 0.01-0.02% methylene blue solution is preferablypreserved in a clean container for about 10 days. A portion of the0.01-0.02% solution of methylene blue is suitable for 3-fold use within1 day. Visually, the loss of transparency (turbidity) or plaqueformation on the surface of a solution of methylene blue is consideredunsuitable for virus inactivation. In this case, the solution isprepared anew.

The known prior art in this area, at best involves devices having aflat-bottomed cell fluid and located above the radiation source, with ameans for rotating the cell, means for fluid turbulence, and a batteryof radiators of monochromatic visible light to inactivate liquid havingphotoactive properties. The process of inactivation of viruses presenton the surface of medical instruments continues for 45 minutes whileprocessing monochromatic light of wavelength 590 nm.

However, the use of these known systems for the inactivation of RNA andDNA viruses on medical instruments is not effective due to the increasedenergy intensity required and the structural complexity of theconfiguration needed. In addition, methylene blue (photochemical agent),although capable of providing maximum activation of the interaction withmonochromatic light of wavelength 590 nm, the devices of the prior artdo not disclose the conditions and circumstances involving the requiredlighting.

A basis of the present invention, however, is to develop a simplifieddesign, with minimal labor and energy expenditures for the inactivationof RNA and DNA viruses on medical instruments, by achieving maximumactivation of the photochemical agent in the interaction withmonochromatic light, thereby distinguishing the instant technique anddevices from the less efficient prior art.

The problem is solved by the fact that the setting for the inactivationof RNA and DNA viruses on medical instruments, includes ahermetically-sealed housing with a camera, housed in a chamber containerto hold the tools, which is filled with a solution of methylene blue,and installed with an emitter of monochromatic light source, where,according to the present invention, a monochromatic light source isarranged in the emission spectrum monochromatic emitters with awavelength range of 582-592 nm and 658-662 nm, with a total capacity ofnot less luminous flux 280 lm. As a monochromatic emitter, Lightemitting diodes (LEDs) were selected in a preferred embodiment.

The device is schematically illustrated by reference to FIGS. 1-4 of theDRAWINGS, where FIG. 1 shows the exterior of an exemplary device orapparatus that practices the principles of the present invention. FIG. 2illustrates preferred interior components to implement the techniques ormethodologies of the present invention. FIGS. 3 and 4 illustrate viewsof the device of FIG. 1, taken along the lines A-A and B-B in thefigures, respectively.

With reference now to the DRAWINGS, a device is shown that may beemployed in practicing the invention, generally designated by thereference numeral 1, which includes a housing 2 with a door, ventilationholes in the sides and an inner chamber 3, as shown in FIGS. 2-4. On alower base of the inner chamber 3 is another chamber, generallydesignated by the reference numeral 4, which may constitute a cuvetteshape 5 and include therein an aforedescribed photoactivated liquid(such as an aqueous solution of methylene blue), generally designated bythe reference numeral 6.

With further reference to the DRAWINGS, particularly to FIGS. 2 and 4thereof, there is shown an emitter of monochromatic light, generallydesignated by the reference numeral 7, which is mounted to an upper base8 of the interior of inner chamber 3. Exposure time of the emitters canbe set by use of a timer knob 9, as shown in FIGS. 1 and 2, where eachdivision of the scale thereon can correspond to 15 minutes, and thetotal time given by the timer in one embodiment is 90 minutes. In apreferred embodiment of the present invention, the monochromatic emitter7 is activated by turning the aforementioned timer knob 9 in a clockwisedirection with the door closed. When the set exposure time expires, thetreatment is done automatically. A signal indicator light, generallydesignated by the reference numeral 10, preferably indicates when thedevice 1 is in operation.

In the case of a premature opening of the housing door 2, in a preferredembodiment the monochromatic emitter 7 is switched off.

Various ways to utilize the apparatus of the present invention are nowshown.

Medical instruments are placed in the cuvette 5 within theaforementioned aqueous solution of methylene blue 6, and theaforementioned door closed. The medical devices in the chamber 4 arethen subjected to irradiation by emitters 7 of light energy, such asmonochromatic radiation with a maximum specific content of monochromaticlight with a wavelength of 590 nm or 660 nm, with a total light outputof not less than 280 lm. The exposure time may be set to 90 minutes,e.g., using the aforesaid timer 9. After treatment, in the device 1, theviruses remaining on the medical instruments are completely inactivated,i.e., the viruses lose their ability to infect cells of the human body.Instruments so sterilized are then reliably reused without risk ofinfecting patients.

In a preferred embodiment of the present invention, the aforementionedmonochromatic light emitter 7 has a maximum specific content of amonochromatic beam with a wavelength of 590 nm or 660 nm, with a totalcapacity of not less luminous flux 280 lm, is made in the form of LEDs,evenly placed on the panel or upper base of the chamber 3, as shown inFIG. 4, and calibrated in the emission spectrum with a wavelength rangeof 582-592 nm or 658-662 nm.

Verification steps of the employment of the claimed apparatuses andmethods within an installation and carried out on in a biologicalenvironment contaminated by viruses, such as blood plasma.

Example 1 Shows a First Exemplary Usage

Monochromatic radiation emitters 7 with a range of 590±2 nm areemployed. After treatment in the inventive installation method, i.e.,within device 1, samples of HBV containing plasma were treated for 90minutes in a 0.01% solution of methylene blue, and afterward the amountof lymphocytes, computed by Polymerase Chain Reaction (PCR), of HBV DNAparticles was zero, i.e., they were not found. This indicates that,after inactivation, the HBV completely lost the ability to penetrate thehuman lymphocytes.

In case of using a monochromatic radiation emitter 7 with a range of588-592 nm, this reached full effect on HBV inactivation in a 0.01%methylene blue solution.

Example 2 Shows a Second Exemplary Usage

Monochromatic radiation emitters 7 with a range of 590±2 nm areemployed. After treatment in the device 1, samples of HBV containingplasma were treated for 90 minutes in a 0.02% solution of methyleneblue. As above, the amount of lymphocytes, computed by PCR, of HBV DNAparticles were not found. This indicates that, after inactivation, HBVcompletely loses the ability to penetrate the human lymphocytes.

This also means that, when using monochromatic radiation emitters 7 witha range of 588-592 nm, the full effect of HBV inactivation in 0.02%methylene blue solution was reached.

Example 3 Shows a Third Exemplary Usage

Monochromatic radiation emitters 7 with a range of 660±2 nm wereemployed. After treatment in the device 1, as set forth hereinabove,samples of HBV containing plasma were treated for 90 minutes in a 0.01%solution of methylene blue. Again, the lymphocytes, computed by PCR,found no HBV DNA particles. This again indicates that, afterinactivation, HBV completely lost the ability to penetrate the humanlymphocytes.

In case of using monochromatic radiation emitters 7 with a range of658-662 nm, the full sterilization treatment effect was reached byinactivating HBV inactivation in 0.01% methylene blue solution.

Example 4 Shows a Fourth Exemplary Usage

Monochromatic radiation emitters 7 with a range of 660±2 nm wereemployed. After treatment in the device 1, as discussed, samples of HBVcontaining plasma were treated for 90 minutes in a 0.02% solution ofmethylene blue, and no lymphocytes, computed by PCR, of the HBV DNAparticles were found.

This further indicates that, after inactivation, HBV completely losesthe ability to penetrate the human lymphocytes.

In case of using monochromatic radiation emitters 7 with a range of658-662 nm, the full effect on HBV inactivation in 0.02% methylene bluesolution was reached.

Thus, as shown in the various examples, the use of the principles of theclaimed invention can effectively and cost-effectively achieve completeinactivation of RNA and DNA viruses on medical instruments and can beoffered for wide practical use in health care facilities.

While the present invention has been illustrated by the description ofthe embodiments thereof, and while the embodiments have been describedin detail, it is not the intention of the Applicant to restrict or inany way limit the scope of the appended claims to such detail.Additional advantages and modifications will readily appear to thoseskilled in the art. Therefore, the invention in its broader aspects isnot limited to the specific details, representative apparatus andmethod, and illustrative examples shown and described. Accordingly,departures may be made from such details without departure from thebreadth or scope of the applicant's concept. Furthermore, although thepresent invention has been described in connection with a number ofexemplary embodiments and implementations, the present invention is notso limited but rather covers various modifications and equivalentarrangements, which fall within the purview of the appended claims.

What is claimed:
 1. An apparatus for inactivating RNA and DNA containedin viruses on medical instruments comprising: a housing, said housinghaving a sealable aperture allowing entry to a chamber within saidhousing; a container within said housing in said chamber, said containercontaining therein a methylene blue aqueous solution, at least onemedical instrument being immersed in said solution; and at least onemonochromatic light source within said housing in said chamber and abovesaid container, said at least one monochromatic light source irradiatingsaid solution and said at least one medical instrument in said containerwith monochromatic radiation, wherein said methylene blue aqueoussolution, within said container, has a methylene blue concentration fromabout 0.01% to about 0.02%, whereby RNA and DNA of viruses on said atleast one medical instrument are inactivated.
 2. The apparatus accordingto claim 1, wherein said monochromatic light source is at least oneemitter and said monochromatic radiation is within a wavelength range ofabout 582-592 nm.
 3. The apparatus according to claim 2, wherein saidmonochromatic radiation is within a wavelength range of about 588-592nm.
 4. The apparatus according to claim 3, wherein said monochromaticradiation is at a wavelength of about 590 nm.
 5. The apparatus accordingto claim 1, wherein said monochromatic light source is at least oneemitter and said monochromatic radiation is within a wavelength range ofabout 658-662 nm.
 6. The apparatus according to claim 5, wherein saidmonochromatic radiation is at a wavelength of about 660 nm.
 7. Theapparatus according to claim 1, wherein said monochromatic light sourceemits a total light output of said monochromatic radiation on saidsolution greater than about 280 lumens.
 8. The apparatus according toclaim 1, wherein said monochromatic light source comprises at least oneLED.
 9. The apparatus according to claim 1, further comprising: at leastone timer on an outside surface of said container, said at least onetimer being used to time the irradiation of said solution and said atleast one medical instrument.
 10. The apparatus according to claim 9,wherein said time for said irradiation of said solution with said atleast one medical instrument in said container is for at least about 90minutes.
 11. The apparatus according to claim 10, wherein said at leastabout 90 minutes is a set exposure time for said solution.
 12. Theapparatus according to claim 1, further comprising: at least oneindicator light on an outside surface of said container, said at leastone indicator light being used to indicate the status of the irradiationof said solution and said at least one medical instrument.
 13. Theapparatus according to claim 1, wherein said container is a cuvette.